The present invention relates to a bracing device and, in particular, to a bracing device for emergency response, commercial, industrial and residential environments.
There is often need for a portable, readily adaptable and temporary bracing device in a wide array of emergency response, commercial, industrial or residential environments.
For example, in emergency response environments there is a frequent need for a portable bracing device that can be reused or, if necessary, sacrificed, so emergency response personnel can safely extract an accident victim lodged between solid surfaces on the verge of collapse. Also, such a bracing device could be used by fire safety personnel to ensure that walls and/or ceilings that have been weakened by fire or heat exposure do not collapse in their work area.
Further, in certain commercial/industrial environments, there may be a need to temporarily strengthen or support a wall surface against a floor surface or to prevent two opposing surfaces, such as a ceiling opposing a floor surface or two opposing wall surfaces from collapsing on each other. Such situations can arise, for example, without limitation, in the case of building construction or demolition or trench excavation.
And in the case of residential environments, there is a particular need for a bracing device that can be used in home improvement and construction applications as well as for security applications. For example, there may be a need to temporarily strengthen or support surfaces in the orientation described above under commercial/industrial environments. But as well, there is a need for enhancing the security of certain doors, windows and other possible entryways against potential intruders. Typically, for doors secured by a deadbolt, there is usually about only xc2xd inch of wood in a door jamb for securing the door against a forced entry. For instance, according to 1996 FBI statistics, there were about 2.5 million burglaries in the U.S., of which about 77% were by forced entry. And 80% of forced entry burglaries were executed by kicking an entry door (i.e., kick burglary). Accordingly, kick burglaries are the method of choice for most burglaries in the U.S.
To address this need for improved home security, numerous products have been produced including door security bars or supplemental strength supports for doorjambs. However, all of these devices either require installation of hardware into or on the door to provide effective bracing strength and/or are cumbersome to implement.
Most particularly, the conventional devices used for bracing a door lack a design for optimally adapting to a wide range of door types, hardware and environments in both a convenient and efficient manner. For instance, many conventional door security bars are extendable to a range of lengths in order to adapt to a range of different door environments, hardware type and hardware placement. Conventional door security bars typically have a cradle for engaging a door knob, a pivoting flat foot for engaging a floor surface and an adjustable length bar between the cradle and foot. Examples of such door security bars are described in U.S. Pat No. 5,340,175 (Wood, Aug. 23, 1994), U.S. Pat. No. 5,333,922 (Jones, Aug. 2, 1994), U.S. Pat No. 5,064,232 (Quarberg, Nov. 12, 1991), U.S. Pat. No. 4,563,027 (Chechovsky, Jan. 7, 1986), U.S. Pat. No. 5,286,075 (Monzingo, Feb. 15, 1994), U.S. Pat. No. 5,988,710 (Kortschot et al., Nov. 3, 1999), U.S. Pat. No. 4,676,536 (Arbic et al., Jun. 30, 1987) and U.S. Pat. No. 4,157,128 (Peters, Jun. 5, 1979). The adjustable bars described in Marik""s U.S. Pat. No. 5,218,341 (Jun. 8, 1993) and U.S. Pat. No. 5,392,026 (Feb. 21, 1995) are curved in an attempt to keep the feet flat on the floor surface. U.S. Pat No. 4,971,374 (Lovell et al., Nov. 20, 1990) describes a door security device having a cradle for engaging a door knob, a flat foot for engaging the floor and an adjustable bar between the cradle and foot. However, Lovell et al.""s flat foot does not pivot.
Other door security devices described in U.S. Pat No. 5,398,982 (Watson, Jr., Mar. 21, 1995), U.S. Pat No. 4,290,636 (Steele, Sep. 22, 1981), U.S. Pat. No. 5,676,410 (Angerbrandt, Oct. 14, 1997), U.S. Pat. No. 4,822,086 (Brown, Apr. 18, 1989) and U.S. Pat No. 5,098,138 (Vandewege, Mar. 24, 1992) require hardware to be mounted to the door and/or the floor in order to use the device.
All of these door bracing devices suffer from at least four basic deficiencies.
First, they use a relatively rigid, substantially planar foot member that has a greater tendency to slip on the surface it contacts unless the bracing bar""s length is adjusted to obtain optimal contact between the foot member""s surface that interfaces with the opposing surface (xe2x80x9cfoot member contact surface areaxe2x80x9d), which is typically a floor surface. Consequently, these devices invariably require the end user to use some judgment in selecting the most appropriate bar length for ensuring the bracing device can provide the necessary bracing strength. Moreover, some users, for various reasons, tend to mistakenly select the wrong length in trying to optimize the foot member contact surface area.
Second, even if the device""s length is properly adjusted, there is a substantial likelihood that the device will be used to brace another door with a different door knob height, but without adjusting the device""s length accordingly. In such a case, the foot member contact surface area is reduced. And, with a reduction in the foot member contact surface area, the bracing device""s foot member is more prone to slippage, at a lower external pressure or force than the foot member is designed to withstand.
Third, even if the device""s length is properly adjusted, there is a substantial likelihood that during installation the bracing device will be placed somewhat off-center with its optimum alignment with the door. This is a relatively common installation error with conventional devices. By xe2x80x9coptimum alignment,xe2x80x9d we mean the bracing device is in alignment with an imaginary line that is directly perpendicular to the door""s face and extends outwardly from the door handle""s axis of rotation. Naturally, as the bracing device""s degree of deviation from the optimum alignment increases, its strength is diminished accordingly, at which degree of deviation a particular bracing device will fail depends substantially on the ability the foot member to adapt to and therefore adequately engage the floor surface when the bracing member is not optimally aligned. But, because conventional devices use a relatively rigid, substantially planar foot member, they generally have a poor adaptability factor and hence cannot effectively engage the floor surface when the bracing member is not optimally aligned.
Fourth, even if the device""s length is properly adjusted, there is a substantial likelihood that device will be installed against a floor surface that has surface irregularities. Such surface irregularities can reduce the foot member contact surface area, particularly when the foot member has a relatively rigid and substantially planar construction. Again, with a reduction in the foot member contact surface area, the bracing device""s foot member is more prone to slippage, at a lower external pressure or force than the foot member is designed to withstand.
Likewise, in the context of bracing devices used in non-security applications the bracing devices are typically implemented by adjusting the bracing member""s length and using fasteners (e.g., nails, screws, bolts, etc.) and/or hardware to attach the bracing device to each surface being braced.
Accordingly, there is need for a bracing device that can readily adapt to bracing two surfaces against each other, while providing the desired bracing strength. More specifically, there is a need for a temporary bracing device that can readily adapt, without requiring supplemental surface hardware and/or fasteners, to a wide range of angles and distances for providing the desired bracing strength between two surfaces, whether for commercial/industrial, residential, emergency response and/or safety applications. Preferably, such a bracing device can provide a continuous range of angles at which the bracing device can be placed for producing the desired bracing strength, but without requiring an adjustment to the device""s length. And most preferably, where the size of the device permits, can be implemented with a one-handed operation.
According to the invention, there is provided a bracing device for bracing a first surface against a second surface, the device comprising:
(a) a bracing member having a first end and a second end, and a first end member affixed to the first end, wherein
(b) at least a portion of the first end member has a substantially convex curvature and material adapted to frictionally engage the first surface; and
(c) the second end is adapted to engage the second surface.